Case Study and Bid-Winning Solution Analysis of the CNVI Dongfeng 3308 mm Wheelbase Sewage Treatment Vehicle Procurement in Hohhot In northern frigid regions, municipal sanitation departments impose significantly higher vehicle selection standards than under normal conditions. For example, Hohhot’s winter minimum temperature can drop to -30°C, imposing stringent requirements on anti-freeze starting performance, low-temperature hydraulic system stability, and routine maintenance plans for sewage treatment vehicles. This article takes Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as 'Chengli')’s actual delivery case in Hohhot as a starting point, combined with the government procurement framework agreement model, to provide a detailed interpretation of the bid-winning solution and response strategies for the CNVI Dongfeng 3308 mm wheelbase sewage treatment vehicle. I. Background of Government Framework Procurement Agreement In 2025, a municipal sanitation department aimed to enhance urban drainage system maintenance efficiency and planned to procure a batch of cold-climate-adapted sewage treatment vehicles via the framework agreement procurement method. The tender documents explicitly stipulated that vehicles must comply with China VI emission standards; the chassis must support cold-start capability at low temperatures; the hydraulic system must operate stably at -25°C; and a targeted winter maintenance plan must be provided. According to publicly available tender information, the total procurement budget was capped at approximately RMB 3.407 million, with six units planned for acquisition—each priced around RMB 500,000. After multiple rounds of technical evaluation and commercial negotiation, Chengli Special Purpose Vehicle secured inclusion among shortlisted suppliers, leveraging its comprehensive certified model portfolio (e.g., CLW5070GSSD6) and extensive service experience in cold regions. Chengli has delivered multiple successful projects across Inner Mongolia—including street sweepers and vacuum tankers procured by a district urban management bureau—whose reliable winter operation performance established trust for this framework agreement. II. Shortlisting Process and Technical Adaptation During the shortlisting process, Chengli implemented specialized technical upgrades to the CNVI Dongfeng 3308 mm wheelbase sewage treatment vehicle specifically tailored to Hohhot’s extreme climate conditions. Key improvements included: Anti-Freeze Starting Performance: Equipped with a low-temperature starting assistance system, including an electrically heated fuel filter, intake air preheating device, and low-temperature starting battery—ensuring successful single-start within 30 seconds at -30°C. Low-Temperature Hydraulic Stability: Utilized low-pour-point synthetic hydraulic oil (pour point below -40°C); added thermal insulation sleeves and electric trace heating to hydraulic lines to prevent oil crystallization or line blockage. Field testing by Chengli’s technical team confirmed that hydraulic system pressure fluctuation remained within ±5% after four consecutive hours of operation at -25°C. Winter Maintenance Plan: Chengli provides a customized 'one-vehicle-one-file' maintenance manual, specifying shortened oil-change intervals (every 500 operating hours), antifreeze replacement criteria, and 24-hour emergency repair response. Chassis warranty is covered by Dongfeng’s nationwide authorized service network; superstructure services are provided for life by Chengli, with spare parts dispatched directly to Hohhot within 24 hours. These enhancements directly addressed the procuring entity’s core concern regarding winter operational reliability. Per local procurement practice, technical proposals typically account for over 40% of the total evaluation score; Chengli earned high marks during shortlisting due to its outstanding low-temperature adaptation capabilities. III. Order Trigger Mechanism and Delive